The House of Representatives on Thursday voted down the Future Forward Party's motion for a committee to study ways to prevent future military coups.
The House rejected the proposal with 242 votes against and 215 MPs supporting it, with two abstentions. FFP secretary-general Piyabutr Saengkanokkul proposed the motion early this month.
Before the vote Mr Piyabutr tried to woo support, telling MPs that coups were a reaction to political crises, but were not a right way to solve political conflict.
Coups could not bring about a liberal democracy, they only enabled a group within the military to take over and prolong their stay in power, he said.